Unsaturated ester of alkoxy-aryloxy alcohols



Patented June 6, 1944 'UNSAI'UBA'IED ESTER F ALKOXY- ARYLOXY ALCOHOLS Gerald B. Coleman and Bartholdt C. Hadler, Midland, Mich, assignors to The Dow Chemical Company, Midland, Mich, a corporation of Michigan No Drawing. Application September 25, 1941, Serial No. 412,298

2 Claims. (Cl. 260-486) This invention concerns esters or alkoxy-arylcam-substituted lower alcohols with certain unsaturated aliphatic mono-carboxylic acids, said esters having the general formula wherein-R1 represents an alkoxy substituent, R2 represents a lower alkylene radical containing from two to six carbon atoms, R represents an aliphatic hydrocarbon radical containing not more than ten carbon atoms and at least one ethylapproximately 86-91 C. for 5- hours. Won completion of the reaction, the mixture was allowed to cool, dissolved. in benzene, and washed with dilute aqueous sodium bicarbonate solution. The benzene was then distilled-oil and the ester product was purified by fractional distillation under vacuum. There was obtained beta-(2- methoxy-phenoxyl-ethyl crotonate, a colorless liquid distilling at approximately 1a5-13a 0.1m-

enic linkage, n represents the number of substituents on the aryl nucleus and is not greater than 2. All such esters are high-boiling liquids or crystalline solids which are substantially insoluble in water, but are readily soluble in organic solvents. The compounds are useful as plasticizing or modifying agents ior vinyl resins, e. g. polystyrene, and cellulose derivative (e. g. ethyl cellulose, cellulose acetate, etc.) compositions.

The unsaturated esters of the present class are conveniently prepared by esterifying an alkoxyaryloxy alcohol, e. g. beta-(Z-methoxy-phenoxy) ethanol, with an aliphatic mono-carboxylic acid which contains not more than ten carbon atoms and at least one ethylenic linkage in the aliphatic residue, e. g. crotonic acid. acrylic acid, betaethyl-acrylic acid, undecylenic acid, sorbic acid, etc. The reaction may be carried out by heating at a temperature of about 60-1'30 C. a mixture of the aryloxy alcohol with approximately one chemical equivalent ofthe unsaturated monocarboxylic acid and a small proportion of an esterification catalyst, e. g. approximately 0.01-

'0.04 molecular equivalent of a strong acid, such as sulphuric or benzene sulphonic acid. Water is formed in the reaction and, if desired, a waterimmiscible organic solvent, such as benzene or toluene, may be added to the reaction mixture for the purpose of promoting distillation and removal of the water during the esterification. Upon completion of the reaction, the mixture is treated with suiiicient alkali to neutralize any free acid, washed with water, and the ester product is separated and purified by fractional distillation or crystallization.

The following example is illustrative of the preparation of the esters of the present class but is not to be construed as limiting the invention:

Example A mixture of 128 grams (0.76 mol) of beta-(2- methoxy-phenoxy) -ethanol, 64.5 grams (0.75 mol) of crotonic acid, and 5 grams of benzene sulphonic. acid was heated at a temperature of der 1 millimeter pressure and having a specific gravity of about 1,1234 at 25/4 C. and the formula OCH:

Other unsaturated alkoxy-aryloxy-alkyl esters of the present class may be prepared by the general method illustrated by the foregoing example. For example, beta- (2 ethoxy phenoxy) propanol may be reacted with tiglic acid to produce beta-(2-ethoxy phenoxy) propyl tiglate; beta-(2-butoxy-phenoxy) ethanol with methacrylic acid to produce beta-(2-butoxy-phenoxy)- ethyl methacrylate; gamma-(2-methoxy-phenoxy) -propanol with vinyl acetic acid to produce gamma- (Z-methoxy-phenoxy) -propyl vinlyacetate; beta-(2-propoxy-phenoxy) -butanol with beta-ethylacrylic acid to produce beta-(2-pro-v wherein R1 represents an alkoxy substituent, and n represents an integer not greater than 2.

2. Beta-(2-methoxy-phenoxy) -ethyl crotonate.

GERALD H. COLEMAN, BARTHOLDT C. HADLER 

